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## 1D Transient Heat Conduction CDF Tool

### Analytic Solution for 1D Transient Heat Conduction

The problem geometry and boundary conditions are shown below. An initially isothermal (Tinitial) semi-infinite medium is suddenly subject to a surface temperature Th.

The temperature field can be non-dimensionalized as:

$\theta (x,t)=\frac{T(x,t)-T_{\text{initial}}}{T_h-T_{\text{initial}}}$

The governing differential equation (with spatially one-dimensional heat flow) is

$\frac{\partial \theta (x,t)}{\partial t} = \alpha \frac{\partial^2 \theta (x,t)}{\partial x^2}$

The solution for all locations x and times t is:

$\theta(x,t) = 1-\text{erf}\left[\frac{x}{2\sqrt{\alpha t}}\right]$

where α is the material’s thermal diffusivity.

### Graphical CDF Tool

The following is an embedded, active Mathematica CDF tool. The units for α are cm2/sec, with corresponding units of cm and sec for x and t, respectively.